Conventional box spring assemblies typically include springs which tend to lean in one direction or another away from a vertical plane in reaction to the application of a vertically applied load. See, for example, U.S. Pat. Nos. 3,722,013, 3,825,960; 3,833,948; 3,835,485; 4,000,531; 4,068,329; 4,195,376; 4,207,634; 4,452,438; and 4,470,584.
Partial solutions to this problem have called for the use of large springs, which provides a broad platform to shoulder the load. One problem with such approaches, however, lies in the need to provide firmer resistance in selected locations of the box spring assembly than in other locations. Frequently this problem is left unsolved by the difficulty of locating bulky springs within the spacial constraints imposed by the assembly. Thus, the bulk of conventional springs imposes restraints on the number and location of sites within the assembly at which the springs can be located. Diminutive springs, however, tend to rock or lean away from a vertical position when the load is applied.